To evaluate perceived facial aesthetic changes after combined orthodontic-orthognathic treatment in female patients with skeletal Class III malocclusion treated with bimaxillary surgery, to compare observer group differences in quantitative change scores, and to descriptively characterize categorical response patterns among orthodontists, artists, and laypeople.

This retrospective image-based observational study included 17 female Class III patients treated between 2016 and 2024 with Le Fort I advancement and bilateral sagittal split osteotomy for mandibular setback. Forty-five observers (15 orthodontists, 15 artists, and 15 laypeople) evaluated standardized pretreatment and post-treatment composite facial-image panels using six 10-point aesthetic rating items and categorical questions on post-treatment facial impression and the most determinant facial aesthetic feature.

Patient-level post-treatment ratings were significantly higher than pretreatment ratings for all six assessment items within each observer group after Holm correction (all adjusted P < 0.001). Patient-level change-score mixed models showed significant observer group differences in the magnitude of perceived improvement for all six items (Holm-adjusted P = 0.002 for profile aesthetics and P < 0.001 for the remaining five items). Descriptively, laypeople most frequently selected the smile, orthodontists proportions/symmetry, and artists overall facial expression as the most determinant facial aesthetic feature.

In this selected female Class III sample, post-treatment facial aesthetic ratings were more favourable than pretreatment ratings, while different categorical response patterns were observed across the observer groups.